From 66eae0ae75596b63b4a6352bf1c9064044765f60 Mon Sep 17 00:00:00 2001 From: Thomas Lamprecht Date: Thu, 5 Nov 2020 18:43:01 +0100 Subject: [PATCH] fix dirty-bitmap state migration freeze The idea in general is to migrate all the state, which is small for us, in a single step once. But, QEMU only calls save state if we return active true. Hardcoding is-active to return true, like done initially, makes the migration freeze, as QEMU thinks this is never done, and only stops calling us and finishes after a few seconds. So, add a state with an "active" boolean, set to true when initializing a migration, and set it to false when the state was saved. Signed-off-by: Thomas Lamprecht --- ...igrate-dirty-bitmap-state-via-savevm.patch | 29 +++++++++++-------- 1 file changed, 17 insertions(+), 12 deletions(-) diff --git a/debian/patches/pve/0055-PVE-Migrate-dirty-bitmap-state-via-savevm.patch b/debian/patches/pve/0055-PVE-Migrate-dirty-bitmap-state-via-savevm.patch index 5a2e29e..b1eca48 100644 --- a/debian/patches/pve/0055-PVE-Migrate-dirty-bitmap-state-via-savevm.patch +++ b/debian/patches/pve/0055-PVE-Migrate-dirty-bitmap-state-via-savevm.patch @@ -15,11 +15,11 @@ Signed-off-by: Stefan Reiter --- include/migration/misc.h | 3 ++ migration/Makefile.objs | 1 + - migration/pbs-state.c | 92 ++++++++++++++++++++++++++++++++++++++++ + migration/pbs-state.c | 97 ++++++++++++++++++++++++++++++++++++++++ pve-backup.c | 1 + qapi/block-core.json | 9 +++- softmmu/vl.c | 1 + - 6 files changed, 106 insertions(+), 1 deletion(-) + 6 files changed, 111 insertions(+), 1 deletion(-) create mode 100644 migration/pbs-state.c diff --git a/include/migration/misc.h b/include/migration/misc.h @@ -48,10 +48,10 @@ index 0fc619e380..20b3792599 100644 common-obj-$(CONFIG_RDMA) += rdma.o diff --git a/migration/pbs-state.c b/migration/pbs-state.c new file mode 100644 -index 0000000000..165895b488 +index 0000000000..c711498c3e --- /dev/null +++ b/migration/pbs-state.c -@@ -0,0 +1,92 @@ +@@ -0,0 +1,97 @@ +/* + * PBS (dirty-bitmap) state migration + */ @@ -63,6 +63,12 @@ index 0000000000..165895b488 +#include "migration/register.h" +#include "proxmox-backup-qemu.h" + ++typedef struct PBSState { ++ bool active; ++} PBSState; ++ ++static PBSState pbs_state; ++ +static void pbs_state_save_pending(QEMUFile *f, void *opaque, + uint64_t max_size, + uint64_t *res_precopy_only, @@ -70,9 +76,6 @@ index 0000000000..165895b488 + uint64_t *res_postcopy_only) +{ + /* we send everything in save_setup, so nothing is ever pending */ -+ *res_precopy_only = 0; -+ *res_compatible = 0; -+ *res_postcopy_only = 0; +} + +/* receive PBS state via f and deserialize, called on target */ @@ -106,20 +109,21 @@ index 0000000000..165895b488 + qemu_put_buffer(f, buf, buf_size); + + proxmox_free_state_buf(buf); ++ pbs_state.active = false; + return 0; +} + +static bool pbs_state_is_active(void *opaque) +{ -+ /* always active, i.e. we do our job for every migration, since there's no -+ * harm done if we just copy an empty buffer */ -+ return true; ++ // we need to be return active once, else .save_setup is never called, but, ++ // if we'd just would return true, we'd freeze the migration for ~ 5 - 10s ++ return pbs_state.active; +} + +static bool pbs_state_is_active_iterate(void *opaque) +{ + /* we don't iterate, everything is sent in save_setup */ -+ return false; ++ return pbs_state_is_active(opaque); +} + +static bool pbs_state_has_postcopy(void *opaque) @@ -140,9 +144,10 @@ index 0000000000..165895b488 + +void pbs_state_mig_init(void) +{ ++ pbs_state.active = true; + register_savevm_live("pbs-state", 0, 1, + &savevm_pbs_state_handlers, -+ NULL); ++ &pbs_state); +} diff --git a/pve-backup.c b/pve-backup.c index 1a2647e7a5..c12ff8bb61 100644